POLITICS can be a fickle business.

One minute you are jubilant, celebrating an election victory the next you are sombre, pondering what you will do when you lose your seat.

It comes to all dominant parties eventually. Often, they have been propelled into power by the force of one or a few irresistible personalities who render the opposition powerless.

Or support has become ingrained in people’s identity which takes a lot longer to change.

Eventually, the magic they possess and the spell they cast over the voting public wears off.

Thatcher, unstoppable in the 1980s, Blair unbeatable in the 2000s.

In Scotland, the working-class loyalty to Labour that had lasted decades, to the extent that devolution was thought to usher in a one-party state, was considered unbreakable.

It did break and was replaced by the SNP, who until recently looked like they would control Scotland for many elections to come.

A poll this week suggests the tide is turning again.

Opinion polls are tricky. Politicians will tell you that the only poll that counts is on election day.

This is obviously true but party strategists track these polls keenly and all the while are conducting their own internal research which the public rarely if ever sees.

The message for politicians is clear. You can never take the voters for granted.

As soon as a party thinks it will be in power for a long period there are dangers.

When one party has an unassailable lead over their rivals, then the opposition to those in charge comes from within.

Factions, that are always there, emerge into the open, differences become splits and the inevitable result is division, infighting and internecine warfare and politicians who are supposed to be on the same teams fighting over the spoils.

All the major parties have or have had internal difficulties recently.

The Conservative Party, in power since 2010, has rattled through no less than five leaders and prime ministers in that time from Cameron to Sunak.

The previous five prime ministers spanned a period of 30 years from Brown to Callaghan.

Finally, it looks like the public at a UK level is running out of patience with the Tories.

Their lockdown party behaviour added to their repeated leadership challenges is wearing thin with even those who are naturally inclined to vote Conservative.

In Scotland, the end of the Salmond/Sturgeon era has brought with it questions for the SNP.

The leadership contest did the party no favours with voters who were not unwavering independence supporters but instead trusted the SNP as a competent administration.

The image and reputation of competence, built up over many years by the SNP, has been shattered in a fraction of that time, with police investigations and controversial policies that expose internal divisions.

The poll that was released this week still shows the SNP with the most seats in Scotland at a General Election but it is a world away from the 56 out of 59 seats the party took in 2015.

In Glasgow, it suggests Labour would win back all but one of the city Westminster seats.

This a remarkable turnaround for a party that was once chased away from doorsteps in the city when out canvassing and who knowingly went into elections, post-independence referendum, knowing they were on a hiding to nothing.

Labour is the obvious beneficiary of troubles within the Conservatives at a UK level and the SNP in Scotland.

However, it is not so long ago the party was tearing itself apart both at Westminster and Holyrood.

While Keir Starmer and Anas Sarwar may have managed to introduce a degree of stability the spectre of division is never far away.

At a local level in Glasgow, the group leader George Redmond has recently survived a leadership challenge which exposed a clear split within the group.

This is important because councillors are the elected representatives closest to the constituents.

They are the ones putting in the hours campaigning with local activists, galvanising existing support and trying to persuade others to switch their allegiance.

While the leaders of political parties are facing an ongoing task keeping their organisation together and presenting a united front, they cannot forget who they are ultimately responsible to.

It is not their fellow MPs or MSPs, it is not their own party members.

It is those who make the only decision that counts.

The voters, the public, the people.